This project has as its main objective the complete identification and characterization of pertussigen - a protein from Bordetella pertussis with many biological activities. In the past few years, methods of obtaining pertussigen in a highly purified form have been developed, but invariably the yields have been very small. Presently, we have developed methods which have yielded purified pertussigen in greater concentration. The use of dansyl reagent to introduce a fluorescent tag on all proteins in our extracts has facilitated the fractionation procedure, and the use of sucrose density gradient ultracentrifugation has been helpful in the purification of pertussigen. Pertussigen in its purified form is highly effective in sensitizing mice to histamine, in inducing lymphocytosis, in inducing a state of active anaphylaxis to antigens given with it, and in protecting mice from intracerebral challenge with B. pertussis. Some of the other activities of pertussigen under study are its ability to lower the concentration of plasma albumin and globulins and its effect on the reactivity of spleen cells to mitogenic agents. BIBLIOGRAPHIC REFERENCES: Munoz, J. J.: Effect of Trichinella spiralis infection on passive cutaneous anaphylaxis in mice. Infect. Immun. 15: 84-90, 1977. Munoz, J.J. and Bergman, R. K.: Bordetella pertussis: immunological and other biological activities. In Rose, N. (Ed.): Immunology Series. New York, Marcel Dekker, Inc., 1977, vol. 4, 235 pp.